Declaration
multiplicativedeclare (f, multiplicative) tells the Maxima simplifier that f is multiplicative.
If f is univariate, whenever the simplifier encounters f applied
to a product, f distributes over that product. E.g., f(x*y)
simplifies to f(x)*f(y).
If f is a function of 2 or more arguments, multiplicativity is
defined as multiplicativity in the first argument to f, e.g.,
f (g(x) * h(x), x) simplifies to f (g(x) ,x) * f (h(x), x).
This simplification does not occur when f is applied to expressions of
the form product (x[i], i, m, n).